Once again, just playing devil's advocate to make sure that the situation is handled fairly. I haven't seen anything to make me think Ace is hacking, but haven't specced him long enough and don't know him well enough to personally vouch for him. As a long time member of the community, I just want to see the situation handled professionally. I think it's an important conversation to have so that there is some kind of a due process.
Regarding stacking, Ace is indeed one of the first people to always join the server. It's not his fault. I can attest to this as I'm almost always first or second as well and usually see him already on a team. I think stacking is a far bigger problem with TD - it should force random teams. If the argument is mic chat/clans, rarely do clans ever actually work together on mic.
Again, I agree with what you're saying, but watching you and your radar (on the maps where a spectator does have a working radar), I don't see what you see - this is where you slip, in my opinion.
Once again, I don't know what you've seen, but I personally play a similar way that Ace does (just not as good). As a T, If I see no covering long a on dust 2, I just "know" approximately when CTs will be rushing long doors. Regarding the radar, I think nades/flashes are usually a pretty good indicator of how many people are where.
When he does play T, he is a lone ranger. He will camp the flank every round while his team tries to do the objectives, just for him to come as the last T to clean up and get the points. He plays for himself, does nothing with the team.
Hasn't this always been okay on TD? It might not be directly the objective, but IMO covering the flank is far more important than the rush at times. To an extent, the success rush can often be random. On the other hand, holding the flank back and baiting until the enemy reaches your team gives your team the time to secure the rush. Once again, as a T, Dust II is a great example of this - if no one covers B/tunnels and the whole team waits to push long, the CT flank will catch up and destroy the t's. Sure, an all-out rush is the best, but it's pretty rare (especially with the stacking on TD) for there to be a competent enough team.
On D2, I find myself far more valuable to the team trying to distract the CTs at the flank and push the flanks a bit to keep the CTs confused as to where the rush is. Or on CS:S Nightfever I think I used to be pretty damn famous at this as a T. Rush the upper balcony on right side and pick the CTs off - then half the CTs think it's a right side rush, meanwhile my team has A.
Considering that half the team does absolutely nothing, I don't know how you can really hold it against a player to do whatever they can to "clean up." A rusher has a far different mentality than a defender, but you need both to have a stable team. Not to mention, I'd love to see ace come in to clean up after the rush instead of have an entire CT team rushing after the 7 remaining T's at half health.
If you're convinced Ace isn't aimbotting, then I think his stats should be the proof of his innocence. He has 57% headshots, which is pretty decent for CS:GO (i think?) You don't get 57% headshots unless you've played damn well for quite some time and handled a lot of scenarios. If he has the experience and the ability to aim well, I don't see why he'd even need wallhacks. It doesn't really make sense to me. It's not like the guy plays superhuman either. Earlier me and him were dominating as CTs on de_nuke with almost the exact same score. 
